To evaluate the safety and immune response to 640 and 1280 mcg HIV-1 recombinant envelope glycoprotein gp160. To evaluate the duration of antibody response and its relationship to dose and frequency of inoculation.

Evaluation of previous patients who received doses of 40 or 80 mcg gp160 vaccine indicates that, although serum anti-gp160 antibody responses were detected, the level and duration of those responses were limited. A preliminary observation suggests that weak functional antibody responses may develop following the 18 month booster of 40 or 80 mcg; therefore, a dose of gp160 vaccine having potentially greater immunogenicity is of particular interest.

Evaluation of previous patients who received doses of 40 or 80 mcg gp160 vaccine indicates that, although serum anti-gp160 antibody responses were detected, the level and duration of those responses were limited. A preliminary observation suggests that weak functional antibody responses may develop following the 18 month booster of 40 or 80 mcg; therefore, a dose of gp160 vaccine having potentially greater immunogenicity is of particular interest.

In the initial phase of the study, 20 healthy volunteers receive 640 mcg gp160 vaccine and 5 healthy volunteers receive alum placebo. At least 30 days later, 20 additional volunteers receive 1280 mcg gp160 vaccine and 5 volunteers receive placebo. Injections are given on days 0, 30, 180, and 365.

Inclusion Criteria

Patients must have:

• Normal history and physical exam.
• Negative for HIV infection by ELISA and Western blot (i.e., no reactivity at gp160, gp120, gp41, or p24).
• T4 count >= 800 cells/mm3.
• Normal chest x-ray and urinalysis.
• Negative hepatitis B surface antigen.
• Negative HIV p24 antigen test.
• Normal skin reactivity by Merieux test.

Exclusion Criteria

Co-existing Condition:

Subjects with the following symptoms or conditions are excluded:

• Positive PPD.
• Syphilis, gonorrhea, or any other sexually transmitted diseases (including chlamydia or pelvic inflammatory disease).

Subjects with the following prior conditions are excluded:

• History of immunodeficiency, chronic illness, or use of immunosuppressive medications.
• Syphilis, gonorrhea, or any other sexually transmitted diseases (including chlamydia or pelvic inflammatory disease) in the past 6 months.

Prior Treatment:

Excluded:

• Prior blood transfusions or cryoprecipitates within the past 6 months.

Identifiable high-risk behavior for HIV infection (as determined by prescreening questions designed to identify risk factors for HIV infection), including:

• Any history of IV drug use.
• Syphilis, gonorrhea, or any other sexually transmitted diseases (including chlamydia or pelvic inflammatory disease) in the past 6 months.
• More than two sexual partners, or sexual contact with a high-risk partner, in the past 6 months.